Load condition controlled power module

ABSTRACT

In accordance with various aspects of the present invention, a method and circuit for reducing power consumption of a power module during idle conditions is provided. In an exemplary embodiment, a power module is configured for reducing power during idle mode by disengaging at least one power output from a power input. A power module may include one or more power outputs and one or more power module circuits, with power input connected to the power outputs through the power module circuit(s). The power module circuit may include a current measuring system, a control circuit, and a switch. The current measuring system provides an output power level signal that is proportional to the load at the power output. If current measuring system behavior indicates that a power output is drawing substantially no power from the power input, the switch disengages the power input from the power output.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/860,618, now U.S. patent Ser. No. ______, filed on Aug. 20, 2010, andentitled “LOAD CONDITION CONTROLLED POWER MODULE,” which application isa continuation of U.S. patent application Ser. No. 12/180,410, now U.S.Pat. No. 7,795,760, filed Jul. 25, 2008, and entitled “LOAD CONDITIONCONTROLLED POWER MODULE”, all of which are hereby incorporated byreference.

FIELD OF INVENTION

The present invention relates to reducing power consumption inelectronic devices. More particularly, the present invention relates toa circuit and method for reducing power consumption by disengaging apower output from a power input using a power module when idle loadconditions are present at the power output.

BACKGROUND OF THE INVENTION

The increasing demand for lower power consumption and environmentallyfriendly consumer devices has resulted in interest in power supplycircuits with “green” technology. For example, on average, a notebookpower adapter continuously “plugged in” spends 67% of its time in idlemode. Even with a power adapter which conforms to the regulatoryrequirement of dissipating less than 0.5 watts/hour, this extended idletime adds up to 3000 watt-hours of wasted energy each year per adapter.When calculating the wasted energy of the numerous idle power adapters,the power lost is considerable. In addition to power adapters, numerouselectronic devices spend a substantial amount of time plugged-in but notoperating. An opportunity exists for reducing the power lost by theseelectronic devices.

SUMMARY OF THE INVENTION

In accordance with various aspects of the present invention, a methodand circuit for reducing power consumption at a power output during idleconditions is provided. In an exemplary embodiment, a load conditioncontrolled power module is configured for reducing or eliminating powerduring idle mode by disengaging at least one power output from a powerinput. A power module may be connected to one or more power outputs, anda power input which may provide alternating current (AC) to the one ormore power outputs. The power module may include a current measuringsystem, a control circuit, and a switch. The current measuring systemprovides an output power level signal that is proportional to the loadat the power output. In an exemplary embodiment, if behavior of thecurrent measuring system indicates that at least one power output isdrawing substantially no power from the AC power input, the switchfacilitates disengaging of the power input from such power output.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention may be derived byreferring to the detailed description and claims when considered inconnection with the Figures, where like reference numbers refer tosimilar elements throughout the Figures, and:

FIG. 1 illustrates a block diagram of an exemplary load conditioncontrolled power module in accordance with an exemplary embodiment;

FIG. 2 illustrates a block diagram of an exemplary load conditioncontrolled power module in accordance with an exemplary embodiment;

FIG. 3 illustrates a block diagram of an exemplary load conditioncontrolled power module in accordance with an exemplary embodiment; and

FIG. 4 illustrates a circuit diagram of an exemplary control circuit foruse within an exemplary load condition controlled power module inaccordance with an exemplary embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

The present invention may be described herein in terms of variousfunctional components and various processing steps. It should beappreciated that such functional components may be realized by anynumber of hardware or structural components configured to perform thespecified functions. For example, the present invention may employvarious integrated components, such as buffers, current mirrors, andlogic devices comprised of various electrical devices, e.g., resistors,relays, transistors, capacitors, diodes and the like, whose values maybe suitably configured for various intended purposes. In addition, thepresent invention may be practiced in any integrated circuitapplication. However for purposes of illustration only, exemplaryembodiments of the present invention will be described herein inconnection with a sensing and control system and method for use with apower module. Further, it should be noted that while various componentsmay be suitably coupled or connected to other components withinexemplary circuits, such connections and couplings can be realized bydirect connection between components, or by connection through othercomponents and devices located thereinbetween.

Various embodiments are possible of a power module configured forreducing or eliminating power during idle mode. In an exemplaryembodiment, a circuit for implementing the power module is integratedinto or otherwise a part of a larger device and controls power input tothe larger device based on various load conditions. In another exemplaryembodiment, the power module is a component that could be removable orfixed as part of an electronic device. The power module may be a printedcircuit board, a potted block, an integrated circuit, a MEMS device, orany other structure configured for implementation in a larger device orsystem. In another exemplary embodiment, the power module may be withina housing configured to facilitate simple installation of the powermodule. This embodiment may be added to existing electrical devices.

In accordance with various aspects of the present invention, a powermodule configured for reducing or eliminating power during idle mode bydisengaging a power input is disclosed. In an exemplary embodiment, andwith reference to FIG. 1, a power module 100 comprises a power input110, a power output 120 and a power module circuit 130. Accordingly,power module 100 can comprise any configuration of system where a powerinput is received, power is provided at a power output, and a circuitdisengages the power provided to the power output in order to reducepower consumption.

In an exemplary embodiment, power input 110 and power output 120 are3-pin or 2-pin plugs or receptacles. In another exemplary embodiment,power input 110 and power output 120 comprise flying leads forconnection to various electrical components. Other connections may bemade by terminal strips, spade connectors, or fixed connectors mountedon a printed circuit board. However, power input 110 and power output120 can be suitably configured in any other input and/or outputconfiguration. Furthermore, power input 110 may be connected to a 110volt or 220 volt power source in an exemplary embodiment.

In an exemplary embodiment, and with reference to FIG. 2, power module100 comprises power input 110 communicatively coupled to power modulecircuit 130, which in turn is communicatively coupled to power output120. Power output 120 may also be connected or otherwise coupled to aground line and a neutral line in one embodiment. The power modulecircuit 130 comprises a current measuring system 231, a control circuit232, and a switch 233. In an exemplary embodiment and for illustrationpurposes, current measuring system 231 comprises a current transformer231 having a primary circuit and a secondary winding. However, currentmeasuring system 231 may also comprise a resistor with a differentialamplifier, a current sensing chip, a Hall-effect device, or any othersuitable component configured to measure current as now known orhereinafter devised. Current transformer 231 provides an output powerlevel signal that is proportional to the load at power output 120.Furthermore, switch 233 connects the primary circuit of currenttransformer 231 to power output 120.

In an exemplary embodiment, control circuit 232 may comprise at leastone of, or a combination of: a latching circuit, a state machine, and amicroprocessor. In one embodiment, control circuit 232 monitors thecondition of the secondary winding of current transformer 231 andcontrols the operation of switch 233. Furthermore, in an exemplaryembodiment, control circuit 232 receives a low frequency or DC signalfrom current transformer 231. The low frequency signal, for example, maybe 60 Hz. This low frequency or DC signal is interpreted by controlcircuit 232 as the current required by the load at power output 120.

Control circuit 232 can comprise various structures for monitoring thecondition of the secondary winding of current transformer 231 andcontrolling the operation of switch 233. In an exemplary embodiment,with reference to FIG. 3, control circuit 232 includes a current sensor301 and a logic control unit 302. Current sensor 301 monitors the outputof a current measuring system, such as for example, the secondarywinding of current transformer 231, which is an AC voltage proportionalto the load current. Also, current sensor 301 provides a signal to logiccontrol unit 302. In one embodiment, the signal may be a DC voltageproportional to the current monitored by current sensor 301. In anotherembodiment, the signal may be a current proportional to the currentmonitored by current sensor 301.

In an exemplary embodiment, logic control unit 302 is powered by anenergy storage capacitor. Logic control unit 302 may briefly connect thestorage capacitor to power input 110 in order to continue powering logiccontrol unit 302. In another embodiment, logic control unit 302 may bepowered by a battery or other energy source. This energy source is alsoreferred to as housekeeping or hotel power; it functions as a lowauxiliary power source. In one embodiment, auxiliary power is taken frompower input 110. For further detail on similar current monitoring, seeU.S. Provisional Application 61/052,939, hereby incorporated byreference.

In an exemplary embodiment, logic control unit 302 is a microprocessorcapable of being programmed prior to, and after integration of powermodule 100 in an electronic device. In one embodiment, a user is able toconnect to logic control unit 302 and customize the parameters of powermodule 100. For example, a user may set the threshold level and a sleepmode duty cycle of power module 100. Data from power module 100 could betransmitted regarding, for example, the historical power consumptionand/or energy saved. The bidirectional data transfer between powermodule 100 and a display device may be achieved through a wirelesssignal, such as for example, an infra-red signal, a radio frequencysignal, or other similar signal. The data transfer may also be achievedusing a wired connection, such as for example, a USB connection or othersimilar connection.

In accordance with an exemplary embodiment, control circuit 232 mayfurther comprise a power disconnect 303 in communication with logiccontrol unit 302. Power disconnect 303 is configured to isolate logiccontrol unit 302 from power input 110 and reduce power loss. Whileisolated, logic control unit 302 is powered by the storage capacitor orother energy source and logic control unit 302 enters a sleep mode. Ifthe storage capacitor reaches a low power level, power disconnect 303 isconfigured to reconnect logic control unit 302 to power input 110 torecharge the storage capacitor. In an exemplary embodiment, powerdisconnect 303 is able to reduce the power loss from a range ofmicroamperes of leakage current to a range of nanoamperes of leakagecurrent.

In another exemplary embodiment, control circuit 232 receives a controlsignal that is impressed upon power input 110 by another controller. Thecontrol signal may be, for example, the X10 control protocol or othersimilar protocol. Control circuit 232 may receive the control signalthrough the secondary winding of current transformer 231, from a coupledpower input 110, or any other suitable means configured to couple powerinput 110 to control circuit 232 as now known or hereinafter devised.This control signal may come from within power module 100 or may comefrom an external controller. The control signal may be a high frequencycontrol signal or at least a control signal at a frequency differentthan the frequency of power input 110. In an exemplary embodiment,control circuit 232 interprets the high frequency control signal toengage or disengage switch 233. In another embodiment, an externalcontroller may transmit a signal to turn power module 100 to an “on” or“off” condition.

In an exemplary embodiment, if behavior of the secondary winding ofcurrent transformer 231 indicates that power output 120 is drawingsubstantially no power from power input 110, switch 233 facilitates orcontrols disengaging of the primary circuit of current transformer 231from power output 120, i.e., switch 233 facilitates the disengaging of apower source from power outlet 120. In an exemplary embodiment, thesecondary winding of current transformer 231 is monitored for an ACwaveform at the AC line frequency of power input 110, where the ACwaveform has an RMS voltage proportional to the load current passingthrough the primary circuit of current transformer 231 to power output120. In another embodiment, the AC waveform is rectified and filtered togenerate a DC signal before being received by control circuit 232. TheDC signal is proportional to the load current passing through theprimary circuit of current transformer 231 to power output 120.

In one embodiment, the phrase “substantially no power” is intended toconvey that the output power is in the range of approximately 0-1% of atypical maximum output load. In an exemplary embodiment, switch 233 isconfigured to control the connection of the primary circuit of currenttransformer 231 to power output 120 and comprises a switching mechanismto substantially disengage the primary circuit of current transformer231 from power output 120. Switch 233 may comprise at least one of arelay, latching relay, a TRIAC, and an optically isolated TRIAC.

By substantially disabling the primary circuit of current transformer231, the power consumption at power output 120 is reduced. In oneembodiment, substantially disabling power output 120 is intended toconvey that the output signal of the secondary winding of currenttransformer 231 has been interpreted by control circuit 232 assufficiently low so that it is appropriate to disengage switch 233 andremove power from power output 120.

In another exemplary embodiment, and with reference to FIGS. 2 and 3,power module circuit 130 further comprises a reconnection device 234,which is configured to enable the closure of switch 233 through logiccontrol unit 302. The closure of switch 233 reconnects power output 120to the primary circuit of current transformer 231 and power input 110.In an exemplary embodiment, reconnection device 234 comprises a switchdevice that may be closed and opened in various manners. For example,reconnection device 234 can comprise a push button that may be manuallyoperated. In one embodiment, the push button is located on the face ofpower module 100. In another embodiment, reconnection device 234 isaffected remotely by signals traveling through power input 110 thatcontrol circuit 232 interprets as on/off control. In yet anotherembodiment, reconnection device 234 is controlled by a wireless signal,such as for example, an infra-red signal, a radio frequency signal, orother similar signal.

In an exemplary embodiment, and with reference to FIGS. 3 and 4, powermodule circuit 130 further comprises a reconnection device memory state304. Reconnection device memory state 304 is configured to indicatewhether reconnection device 234 was recently activated so that logiccontrol unit 302 can determine the circuit conditions upon power up. Inthe exemplary embodiment, reconnection device memory state 304 comprisesa capacitor C5, which charges when reconnection device 234 is activated.Logic control unit 302 can then measure the voltage on capacitor C5 asan indication of whether reconnection device 234 was activated. In oneexemplary embodiment, reconnection device memory state 304 provides adigital reading to the PB1 input of logic control unit 302. If there issufficient voltage at capacitor C5, the PB1 input reads a “1”. If thereis insufficient voltage at capacitor C5, the PB 1 input reads a “0”. Thedetermination of what voltage is sufficient is dependent in part on theratio of resistors R6 and R7 and can be interpreted by logic controlunit 302, as would be known to one skilled in the art. Capacitor C5serves to store the state of reconnection device 234 until the voltageof capacitor C5 can be read by logic control unit 302.

In accordance with another exemplary embodiment, switch 233 isautomatically operated on a periodic basis. For example, switch 233 mayautomatically reconnect after a few or several minutes or tens ofminutes, or any period more or less frequent. In one embodiment, switch233 is automatically reconnected frequently enough that a batteryoperated device connected to power module 100 will not completelydischarge internal batteries during a period of no power at the input tothe connected device. After power output 120 is reconnected, in anexemplary embodiment, power module circuit 130 tests for or otherwiseassesses load conditions, such as the power demand at power output 120.If the load condition on power output 120 is increased above previouslymeasured levels, power output 120 will remain connected to the primarycircuit of current transformer 231 until the load condition has returnedto a selected or predetermined threshold level indicative of a “lowload”. In other words, if the power demand at power output 120increases, power is provided to power output 120 until the power demanddrops and indicates a defined idle mode. In an exemplary embodiment, thedetermination of load conditions at re-connect are made after a selectedtime period had elapsed, for example after a number of seconds orminutes, so that current inrush or initialization events are ignored. Inanother embodiment, the load conditions may be averaged over a selectedtime period of a few seconds or minutes so that short bursts of highload average out. In yet another exemplary embodiment, power module 100comprises a master reconnection device that can re-engage all poweroutputs 120 to power input 110.

In an exemplary method of operation, power module 100 has switch 233closed upon initial power-up, such that power flows to power output 120.When load conditions at power output 120 are below a threshold level,control circuit 232 opens switch 233 to create an open circuit anddisengage power output 120 from the input power signal. This disengagingeffectively eliminates any idle power lost by power output 120. In oneembodiment, the threshold level is a predetermined level, for exampleapproximately one watt of power or less flowing to power output 120.

In an exemplary embodiment, different power outputs 120 may havedifferent fixed threshold levels such that devices having a higher powerlevel in idle may be usefully connected to power module 100 for powermanagement. For example, a large device may still draw about 5 wattsduring idle, but would never be disconnected from power input 110 if theconnected power output 120 had a threshold level of about 1 watt. Invarious embodiments, certain power outputs 120 may have a higherthreshold levels to accommodate high power devices, or lower thresholdlevels for lower power devices.

In another embodiment, the threshold level is a learned level. Thelearned level may be established through long term monitoring by controlcircuit 232 of load conditions at power output 120. A history of powerlevels is created over time by monitoring and may serve as a template ofpower demand. In an exemplary embodiment, control circuit 232 examinesthe history of power levels and decides whether long periods of lowpower demand were times when a device connected at power output 120 wasin a low, or lowest, power mode. In an exemplary embodiment, controlcircuit 232 disengages power output 120 during low power usage timeswhen the period of low power matches the template. For example, thetemplate might demonstrate that the device draws power through poweroutput 120 for eight hours, followed by sixteen hours of low powerdemand.

In another exemplary embodiment, control circuit 232 determines theapproximate low power level of the electronic device connected at poweroutput 120, and sets a threshold level to be a percentage of thedetermined approximate low power level. For example, control circuit 232may set the threshold level to be about 100-105% of the approximate lowpower level demand. In another embodiment, the threshold demand may beset at about 100-110% or 110-120% or more of the approximate low levelpower demand. In addition, the low power level percentage range may beany variation or combination of the disclosed ranges.

Having disclosed various functions and structures for an exemplary powermodule configured for reducing or eliminating power during idle mode bydisengaging power input, a detailed schematic diagram of an exemplarypower module 400 can be provided in accordance with an exemplaryembodiment of the present invention. With reference to FIG. 4, in anexemplary embodiment of power module 400, power module circuit 130comprises current transformer 231, current sensor 301, logic controlunit 302, power disconnect 303, reconnection device memory state 304,and switch 233.

In one embodiment, current transformer 231 and current sensor 301combine to measure the current from power input 110 and convert saidcurrent to a proportional DC voltage that can be read by logic controlunit 302. Furthermore, switch 233 may comprise a latching relay, e.g.,relay coil K1, that provides a hard connect/disconnect of power input110 to power output 120 after a command from logic control unit 302.Switch 233 alternates between open and closed contacts. Furthermore,switch 233 holds its position until reset by logic control unit 302, andwill hold position without consuming any power in a relay coil K1.

In an exemplary embodiment, logic control unit 302 comprises amicrocontroller that receives input of the current in the power inputline, controls the state of switch 233 and reads or otherwise assessesthe state or position of the contacts of reconnection device 234 andswitch 233. In addition, logic control unit 302 learns and stores thepower profile for an electronic device connected to power output 120. Inanother exemplary embodiment, power module circuit 130 further comprisesreconnection device 234 and reconnection device memory state 304.Reconnection device 234 is activated to turn on power output 120 whenpower module circuit 130 is first connected to power input 110 or whenfull power is needed immediately at power output 120. Reconnectiondevice memory state 304 is configured to indicate to logic control unit302 whether reconnection device 234 was recently activated.

In an exemplary embodiment, power disconnect 303 comprises a network oftransistors Q1, Q2, Q3 which are used in conjunction with zener diodesZ1, Z2 to condition power input 110 to a safe level suitable for logiccontrol unit 302 and isolate logic control unit 302 from power input110. In another embodiment, power disconnect 303 comprises relays inaddition to, or in place of, the transistors of the prior embodiment.

Initial connection of power module 400 involves connecting power module400 to a power source, which may be AC or DC. In an exemplary method,upon initial plug-in of power module 400 to a power source, all circuitsof power module circuit 130 are dead and switch 233 is in the lastposition or state set by logic control unit 302. This initial conditionmay or may not provide power to power output 120. When all the circuitsare dead, there is no current flow into power module circuit 130. Thisis due to the isolation provided by power disconnect 303 andreconnection device 234 in a normal, open position. In an exemplaryembodiment, power disconnect 303 comprises transistors Q1, Q2, Q3 andcapacitor C3. In this state, only leakage current will flow throughtransistors Q1, Q2 and the leakage current will be on the order ofapproximately tens of nanoamperes. Furthermore, current transformer 231provides dielectric isolation from primary side to secondary side sothat only small leakage current flows due to the inter-windingcapacitance of current transformer 231.

With continued reference to FIG. 4, in an exemplary embodiment and forillustration purposes, a user may reconnect the circuit usingreconnection device 234 to establish a current path through diode D1,zener diode Z1, reconnection device 234, resistor R4, diode D6, andzener diode Z3. Diode D1 serves to half-wave rectify the AC line to dropthe peak to peak voltage in half. Zener diode Z1 further reduces thevoltage from diode D1, for example to about 20 volts. Zener diode Z3 andresistor R4 form a current limited zener regulator that provides anappropriate DC voltage at the VDD input to logic control unit 302 whilereconnection device 234 is held. In addition, capacitor C2 smoothes theDC signal on zener diode Z3 and provides storage during the contactbounce of reconnection device 234. Capacitor C2 is sized to providesufficient storage during the start-up time of logic control unit 302,and capacitor C2 in combination with resistor R4 provides a fast risingedge on the VDD input to properly reset logic control unit 302.Furthermore, diode D5 isolates capacitor C2 from capacitor CS so therise time constant of capacitor C2 and resistor R4 is not affected bythe large capacitance of capacitor CS. When capacitor CS is poweringlogic control unit 302, the current of capacitor CS passes through diodeD5. Diode D6 serves to isolate the voltage on capacitor C2 whenreconnection device 234 is released. This allows the voltage stored oncapacitor C5 during the closed time of reconnection device 234 to beretained when reconnection device 234 is open and inform logic controlunit 302 of the open condition.

In an exemplary method, if reconnection device 234 is activated for afew milliseconds, logic control unit 302 is configured to initialize andimmediately set up to provide its own power before reconnection device234 is released. This is accomplished from voltage doubler outputsVD1-VD3 and ZG1 of logic control unit 302. First, output ZG1 is drivenhigh to turn on transistor Q2. With transistor Q2 on, a current path isestablished through resistor R3 and zener diode Z2 providing a regulatedvoltage at the drain of transistor Q1. This regulated voltage is similarto that produced by zener diode Z3 and is appropriate for the VDD inputof logic control unit 302. Second, after the voltage on zener diode Z2has stabilized for a few microseconds, outputs VD1-VD3 of logic controlunit 302 begin switching to produce a gate drive signal to turn ontransistor Q1. The signals produced by outputs VD1-VD3 and componentsincluding capacitor C3, transistor Q3, capacitor C4, diode D3 and diodeD4 produce a voltage at the gate of transistor Q1 that is about twicethe voltage on VDD input of logic control unit 302. This voltagedoubling turns transistor Q1 on hard. Once transistor Q1 is on, thevoltage at zener diode Z2 charges capacitor CS. In an exemplaryembodiment, capacitor CS is a large storage capacitor that is used topower logic control unit 302 when reconnection device 234 is not beingactivated. After capacitor CS has been charged for a few milliseconds,outputs VD1-VD3 and ZG1 return to a rest state and transistors Q1 and Q2are turned off. In this embodiment, logic control unit 302 is operatingoff the stored charge in capacitor CS and not drawing power from powerinput 110. When reconnection device 234 is no longer active, capacitorCS will continue to power logic control unit 302.

If power output 120 is idling and drawing substantially no power, logiccontrol unit 302 may be able to disengage from drawing power and enter a“sleep” mode. In an exemplary method, and with further reference to FIG.4, when logic control unit 302 is operating from the stored energy incapacitor CS, a timing function is enabled in logic control unit 302that uses capacitor C6 to perform the timing function. Capacitor C6 isbriefly charged by the CAPTIME output of logic control unit 302 and overtime capacitor C6 discharge rate will mimic the decay of the voltage oncapacitor CS. Once capacitor C6 voltage at input CAPTIME reaches a lowlevel, logic control unit 302 will set the state of outputs VD1-VD3 andZG1 to again recharge capacitor CS from the AC line. This processrepeats over and over so power is never lost to logic control unit 302.The recharge process takes only a few milliseconds or less to operate,depending on the size of capacitor CS.

Furthermore, in an exemplary method, when logic control unit 302 is notbusy recharging capacitor CS, switching relay K1, or measuring powerdrawn from power output 120, logic control unit 302 is operating in adeep sleep mode that stops all, or substantially all, internal activityand waits for capacitor C6 to discharge. This sleep mode consumes verylittle power and allows the charge on storage capacitor CS to persistfor many seconds. If reconnection device 234 is activated during thesleep mode, capacitor C5 will be recharged and logic control unit 302will resume normal operation and set or reset relay K1. Alternatively,if capacitor C6 voltage falls too low, logic control unit 302 will againrecharge capacitor CS and then return to sleep mode.

While an electronic device is in an idle mode, power module 100 maycontinue to monitor for changes in the power drawn by the electronicdevice. In an exemplary method, while logic control unit 302continuously goes in and out of sleep mode to re-power itself, logiccontrol unit 302 will also periodically test the power being drawn frompower output 120. The period of power testing is much greater than thatof capacitor CS charging and, for example, may be only tested every tenor more minutes. In accordance with an exemplary method, there are atleast three possible outcomes from the result of power testing: 1) thedevice is operating and the switch is not in standby condition, 2) thedevice is not operating but the switch is not in a standby condition, or3) the switch is in a standby condition.

For the outcome when the device is operating and the switch is not in astandby condition, relay K1 has been previously set to deliver power topower output 120 and power testing shows an appreciable load current isbeing drawn by the electronic device connected. An “appreciable load”may be defined by some fixed value programmed into logic control unit302, or it may be the result of a number of power tests and be thetypical load current for this electronic device. A power test resulthere will be interpreted as normal conditions and logic control unit 302will go back into sleep mode cycling until another time period, such asten minutes, has passed when the power test will be made again. Inanother exemplary embodiment, the duration of the sleep mode cycling isdetermined by a user. For example, a user may set the sleep modeduration to be one, two, or five minutes and may do so using a dial, adigital input, a push button, keypad or any other suitable means nowknow or hereinafter devised.

For the outcome when the device is not operating but the switch is notin a standby condition, relay K1 has been previously set to deliverpower to power output 120 and power testing shows a negligible loadcurrent being drawn by the device connected. The “negligible load” maybe some fixed value programmed into logic control unit 302, or it may bethe result of a number of power tests and be the typical minimum foundfor this electronic device. In either case the action taken by logiccontrol unit 302 will be to set relay K1 to an open condition by usingoutputs RELAY1-RELAY2 of logic control unit 302 to energize relay coilK1. The state of relay K1 is determined by logic control unit 302testing for the presence of resistor R5 at RELAY3, since logic controlunit 302 may not know the previous state of relay K1, for example,starting from power off state.

For the outcome when the switch is in a standby condition, that is,relay K1 has been set to remove power from power output 120, logiccontrol unit 302 must set relay K1 to a closed condition to allow ACpower to be applied to the power output. In an exemplary method, oncerelay K1 is set, a period of time is allowed to elapse before the powertesting is done. This delay allows for the electronic device attached topower output 120 to initialize and enter a stable operating mode. Powermeasurements may now be made over some period of time to determine ifthe electronic device is in a low or high power state. If a high powerstate is determined, relay K1 remains set. If a low power state isdetermined, relay K1 is reset to open condition and power is againremoved from power output 120. Also, logic control unit 302 will againbegin sleep mode cycling and power testing after a determined timeperiod, for example, every ten minutes.

If a user wants to operate a device that is connected to power output120 and that power output is turned off, in an exemplary embodiment,activating reconnection device 234 will immediately wake logic controlunit 302 from sleep mode. Since the wake up was from the activation ofreconnection device 234 and not due to power testing or capacitor CSrecharging, logic control unit 302 will immediately set relay K1 toclosed position to power the electronic device connected to power output120.

In addition to the embodiments described above, various other elementsmay be implemented to enhance control and user experience. One way toenhance user control is to allow a user to select the operating mode ofa power output. In an exemplary embodiment, power module 100 furthercomprises a “Green Mode” switch that enables or disables the “green”mode operation. The green mode switch may be a hard, manual switch or itmay be a signal to logic control unit 302. “Green” mode operation is thedisengaging of power output 120 from Power input 110 when substantiallyno load is being drawn at power output 120. A user may use the greenmode switch to disenable green mode operation on various power outputswhen desired. For instance, this added control may be desirable on poweroutputs that power devices with clocks or devices that need to beinstantly on, such as a fax machine.

In one embodiment, power module 100 includes LED indicators, which mayindicate whether a power output is connected to the power line anddrawing a load current. The LED indicators may indicate that whether apower output is active, that is, power is drawn by an electronic deviceand/or the power output has power available even if an electronic deviceis not connected. In addition, a pulsing LED may be used to show whenpower testing is being done or to indicate the “heartbeat” of sleep moderecharging.

In another embodiment, power module 100 comprises at least one LCDdisplay. The LCD display may be operated by logic control unit 302 toindicate the load power being provided to power output 120, for exampleduring times of operation. The LCD may also provide information aboutthe power saved or power consumed by operating power module 100 in orout of a “green” mode. For example, LCD may display the sum total ofwatts saved during a certain time period, such as the life of powermodule 100 or in a day.

Various embodiments may also be used to enhance the efficient use of thepower module and/or individual power outputs in the power module. Onesuch embodiment is the implementation of a photocell or other opticalsensor monitored by logic control unit 302. The photocell determineswhether light is present in the location of power module 100 and logiccontrol unit 302 can use this determination to disengage power output120 depending on the ambient light conditions. For example, logiccontrol unit 302 may disengage power output 120 during periods ofdarkness. In other words, the power outputs of the power module may beturned off at night. Another example is devices do not need power iflocated in a dark room, such as an unused conference room in an office.Also, the power outputs may be turned off when the ambient lightconditions exceed a certain level, which may be predetermined or userdetermined.

In another embodiment, power module 100 further comprises an internalclock. Logic control unit 302 may use the internal clock to learn whichtime periods show a high power usage at power output 120. This knowledgemay be included to determine when a power output should have poweravailable. In an exemplary embodiment, the internal clock has quartzcrystal accuracy. Also, the internal clock does not need to be set to anactual time. Furthermore, the internal clock may be used in combinationwith the photocell for greater power module efficiency and/or accuracy.

The present invention has been described above with reference to variousexemplary embodiments. However, those skilled in the art will recognizethat changes and modifications may be made to the exemplary embodimentswithout departing from the scope of the present invention. For example,the various exemplary embodiments can be implemented with other types ofpower module circuits in addition to the circuits illustrated above.These alternatives can be suitably selected depending upon theparticular application or in consideration of any number of factorsassociated with the operation of the system. Moreover, these and otherchanges or modifications are intended to be included within the scope ofthe present invention, as expressed in the following claims.

1. A power module configured as a component of an electronic device toreduce power consumption during idle operation of the electronic device,said power module comprising: a power module circuit configured toreceive power from a power input and transmit the power to at least onepower output; a control circuit configured to receive an output powerlevel signal and control the connection between said at least one poweroutput and the power input, wherein said power module circuit disengagestransmitting power to said at least one power output in response to saidat least one power output drawing substantially no power; and areconnection device configured to override said control circuit andre-engage said at least one power output and the power input, andwherein said reconnection device is further configured to disengage saidat least one power output and the power input.
 2. The power module ofclaim 1, wherein said power module circuit comprises: a currentmeasuring system configured to monitor current from the power input,wherein said current measuring system provides the output power levelsignal.
 3. The power module of 1, wherein said reconnection device iscontrolled by at least one of an infra-red signal, a radio frequencysignal, and a signal received through the power input.
 4. The powermodule of claim 1, wherein said reconnection device is configured tooverride a single control circuit.
 5. The power module of claim 1,wherein said substantially no power is approximately 0-1% of a typicalmaximum output load of said electronic device at said at least one poweroutput.
 6. A power module configured for integration into an electronicdevice to efficiently provide power to the electronic device, said powermodule comprising: at least one power output configured to provide powerto said electronic device; and a control circuit disconnects a powerinput if the current drawn by said at least one power output is below athreshold level, such that said at least one power output is effectivelydisengaged from the power input.
 7. The power module of claim 6, whereinsaid control circuit tests a load condition at said at least one poweroutput by reengaging said at least one power output to said power anddetermining if the current drawn by said at least one power output isbelow the threshold level.
 8. The power module of claim 6, wherein saidcontrol circuit controls said at least one power output individually. 9.The power module of claim 6, wherein said threshold level is a learnedlevel determined by long term monitoring of a load condition at said atleast one power output.
 10. The power module of claim 6, wherein saidthreshold level is a percentage of a determined approximate low powerlevel of said electronic device, and wherein said percentage of saiddetermined approximate low power level is at least one range ofapproximately 100-105%, approximately 100-110%, and approximately110-120%.